English WebsiteIndependent JPEG GroupDevelopment SiteThe Independent JPEG Group IJG is responsible for the reference implementation of the original JPEG standard.
The reference software from the Independent JPEG Group was a key to the success of the original JPEG standard and has found widespread adoption in applications of image coding. Particularly, all contemporary digital photo cameras support the capture of images in JPEG format as the common medium for image interchange, and all image viewers, image editors, and Web browsers can display JPEG images as common standard.The IJG implementation was first publicly released in October 1991 and has been considerably developed since that time.In June 2009, Independent JPEG Group published a new major release version 7 of the software package to enable a new set of features for image coding application and therewith to continue the success story of JPEG.In January 2010, Independent JPEG Group introduced a new release version 8 with extensions providing the fundament for the next generation image coding standard.In January 2013, Independent JPEG Group released version 9 with improvements for the new introduced lossless coding mode.Version 9a was released in January 2014 and is the first true source reference JPEG codec.Filename Size Last modified Typejpegsrc.v9a.tar.gz 977 KB 19 Jan 2014 Unix Tape Archivejpegsr9a.zip 1042 KB 19 Jan 2014 Zip Compressed DataCHANGE LOG for Independent JPEG Group’s JPEG softwareVersion 9a 19-Jan-2014Add support for wide gamut color spaces JFIF version 2.Improve clarity and accuracy in color conversion modules.Note: Requires rebuild of test images.Extend the bit depth support to all values from 8 to 12BITS_IN_JSAMPLE configuration option in jmorecfg.h.jpegtran now supports N bits sample data precision with all N from 8 to 12in a single instance. Thank to Roland Fassauer for inspiration.Try to resolve issues with new boolean type definition.Thank also to v4hn for suggestion.Enable option to use default Huffman tables for lossless compressionfor hardware solution, and in this case improve lossless RGB compressionwith reversible color transform. Thank to Benny Alexandar for hint.Extend the entropy decoding structure, so that extraneous bytes betweencompressed scan data and following marker can be reported correctly.Thank to Nigel Tao for hint.Add jpegtran -wipe option and extension for -crop.Thank to Andrew Senior, David Clunie, and Josef Schmid for suggestion.Version 9 13-Jan-2013Add cjpeg -rgb1 option to create an RGB JPEG file, and inserta simple reversible color transform into the processing whichsignificantly improves the compression.The recommended command for lossless coding of RGB images is nowcjpeg -rgb1 -block 1 -arithmetic.As said, this option improves the compression significantly, butthe files are not compatible with JPEG decoders prior to IJG v9due to the included color transform.

via InfAI : jpeg.